/Engine/Plugins/Runtime/Metasound/Source/MetasoundEngine/Public/MetasoundGeneratorHandle.h
Note: We don't allow direct assignment to the OnGeneratorsGraphChanged delegate because we need to know that someone actually wants this message so we can start actively listening for the corresponding audio render thread callback...
[FDelegateHandle](API\Runtime\Core\Delegates\FDelegateHandle) AddGraphSetCallback ( UMetasoundGeneratorHandle::FOnSetGraph::FDelegate && Delegate )